......
I have had better luck putting together my own led "bulbs" using the base of a burned out bulb, a star led with its correct lens (collimator), solder and epoxy.
The experts will tell you you need a bridge rectifier &c, but I'm no expert. I simply wire the headlight and tail light in parallel (not in series) with opposite polarity. The headlight and taillight flash alternately but it's not annoying.
.......
pics??
One of my projects that is waiting for some spare time is a slightly higher grade of this same idea. My hope is to have two white LEDs in series with some half decent heatsinking. This would provide the same nominal 6V drop that an incandescent would, and allow the LEDs to be aimed into the reflector, which ought to produce a better beam.
My expectations are pretty low, though. Still, it would be interesting to see how far I could take the idea.
As far as bridge rectifiers, it wouldn't be hard to put wire up four diodes and insert it in series with the dynamo wires. Certainly easier than trying to tuck it into the light housing. The only downside is that if the LED doesn't have suitable heatsinking, then the extra current that is delivered to the LED may lead to overheating and an early death.
I'd be interested in hearing from anyone else who has tried their hand at this and what sort of results they had.
Steve in Peoria